New install + New Exch2019 issue relaying mail


New Member
Jul 16, 2023

Not sure this is a PMG issue but, was hoping that someone may of had a similar issue or can assist?

I'm getting this error from exchange in PMG for incoming mail:
Jul 16 20:23:15 ad postfix/smtp[2971]: E4F5B2095C: to=<Email@address>, relay=[]:25, delay=0.08, delays=0.06/0/0/0.01, dsn=4.7.0, status=deferred (host[] said: 451 4.7.0 Temporary server error. Please try again later. PRX2  (in reply to end of DATA command))

I have 50+ emails queued, then i'll get the occasional one through. I can send email out, I'm not sure what else is needed to help diagnose.
the server at (temporarily) rejects the mail (i guess that's the exchange?)

from my limited search, it seems there might be a dns problem at the exchange server? in any case this is not really a pmg issue but an issue on the exchange side


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